1. Field of the Invention
Embodiments of the invention relate relates generally to electronic devices, and, more specifically, to fin field effect transistors (“FETs”) and processes for fabricating the same.
2. Description of the Related Art
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present invention, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Integrated circuits can be found in virtually any electronic device. For example, integrated circuits, such as microprocessors and digital memory chips, are present in products such as computers, cell phones, and microwave ovens. Since their first introduction over a half century ago, integrated circuits have progressively become smaller and increasingly more densely populated. The increase in density provides numerous advantages, including the ability for smaller chips to perform the same functionality as larger chips. Additionally, the smaller size increases performance while reducing power consumption. Specifically, with smaller size, the electrical paths are shorter, allowing lower power logic to be used at fast switching speeds. However, achieving progressively smaller structure size on the chips, and, thus, producing smaller chips, has become increasingly difficult and costly due, at least in part, to reaching physical limitations of standard fabrication techniques. As such, new and improved processes are constantly being proposed to further reduce cost as well as size.
Typically, the integrated circuit manufacturing process includes at least three main processes: 1) patterning; 2) adding materials; and 3) removing materials. The patterning process is primarily achieved by employing a photolithographic mask or other form of mask. Through the patterning process, various regions are defined that eventually serve as the components, such as transistors and traces, of the integrated circuit. The process of adding materials includes depositing or growing material on a substrate to create multiple layers. The process of removing materials generally includes an etching process. It is through the etching process that material in regions defined by the mask is removed to form various structures.
A fin field effect transistor (“fin FET”) is a type of metal oxide semiconductor FET (“MOSFET”) that is built around a fin (e.g., a tall, thin semiconductive member) extending generally perpendicularly from a substrate. Typically, a gate traverses the fin by conformally running up one side of the fin over the top and down the other side of the fin. Generally, a source and a drain are located on opposite sides of the gate in the fin. In operation, a current through the fin between the source and drain is controlled by selectively energizing the gate.
Advantageously, fin FETs may have significantly faster switching times and higher current density than conventional complementary metal oxide semiconductor (“CMOS”) transistors. In addition, those of ordinary skill in the art will appreciate that fin FETs also typically offer greater control over channel voltages and resistance to short-channel effects. Disadvantageously, the number of iterative steps employed to fabricate a fin FET may exceed those of conventional CMOS processes, and in integrated circuit manufacturing, the number of iterative steps in the fabrication process typically correlates directly with the cost of production. As such, reducing the number of steps employed in fabricating a fin FET would be desirable.